The inclusion of charge-exchange effects in direct-reaction theory is discussed and a nuniber of ... more The inclusion of charge-exchange effects in direct-reaction theory is discussed and a nuniber of experimental results are then treated: the threshold effect in ' Zr(fg, p) and 92Mo(d, p) excitation curves in the region of the (d, n) threshold to the. analog of the parent state, and the behavior of the Zr(d, np) and 9 Mo (d ep) total cross sections in the same region; Hamburger's data for 207Pb (d' p) 208Pb and, 6nally, the discrepancy between (fg, n) and (3He, d) spectroscopic factors for analog states in several light nuclei. The theory is successful in describing the threshold effect and Hamburger's data, but does not explain the discrepancy in spectroscopic factors. A number of methods of calculating the analog-residual-state wave functions are critically discussed. I. INTRODUCTIOÑ~H ERE now exists a considerable body of experimental al evidence'-" indicating that the (d, p) reaction channel leading to a given residual nuclear state is coupled to the (d, Il) reaction channel leading to the isobaric analog of the residual state excited in (d, p'). The simplest theory of such reactions, originally sketched. by Zaidi and von Brentano, " and quantitatively extended by Tamura and Watson, " requires replacement of the outgoing nucleon-nucleus state in the usual distorted-wave Born-approximation (DWBA) amplitude by the appropriate linear combination of solutions to coupled Lane equations. '4 The correctness of such an approach can now be given a fairly rigorous test, since a variety of experimental results is available. In Sec. II, we discuss the introduction of chargeexchange eGects into the usual DWBA theory. In Sec. III we discuss the general features of the (d, Il) threshold effect observed 111 (d, P) cxcltatloll clll'ves, 'tllc complementary (d, ep) data of Cue and Richard, " and the results of calculations. using the theory of * Research supported in part by the U.S. Atomic Energy Commission.
The first elastic-scattering analyzing-power (A) data at 0.8 GeV are presented and discussed. Ang... more The first elastic-scattering analyzing-power (A) data at 0.8 GeV are presented and discussed. Angular distributions of A over the range 2 to 20' (30 for C) have been obtained for C, 5 Ni,~Zr, and Pb using the high-resolution spectrometer at the Clinton P. Anderson Meson Physics Facility. The analyzing powers oscillate sharply over positive values in qualitiative agreement with expectations.
We present results of a phenomenologlcal analysis of recently obtained data for 4He + 4He elastic... more We present results of a phenomenologlcal analysis of recently obtained data for 4He + 4He elastic scattering at 0.65 and 0 85 GeV mmdent laboratory energms. We find that the observed angular dlstnbutmns cannot be fit unless the nuclear potential has a stron/~, short-range repulswe contribution, in agreement w~th the results of microscopic and phenomenologmal analyses of low energy 4He + 4He scattering.
An in-beam electron spectrometer was used to identify internal-conversion transitions resulting f... more An in-beam electron spectrometer was used to identify internal-conversion transitions resulting from proton bombardment of +Mo at 8.0 and 11. 0 MeV.
Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized ... more Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized protons from 40,42,44,48Ca are reported. A first-order, spin-dependent KMT optical potential analysis is presented from which the rms radii of the neutron densities are deduced. A comparison of these results with other determinations and with various theoretical predictions is given.
An analysis of the 4°At(r, t)4°K reactions populating the 0 + analog state at 4.38 MeV and the 0 ... more An analysis of the 4°At(r, t)4°K reactions populating the 0 + analog state at 4.38 MeV and the 0 + antianalog state at 1.65 MeV with incident 3He energies of 35 and 18 MeV is made, including contributions from a pickup-stripping reaction mechanism as well as a conventional direct reaction mechanism. Agreement in magnitude and shape between calculated and experimental cross sections is best when both mechanisms are allowed to contribute.
A theoretical description of isospin-forbidden analog resonances in direct reactions, using the K... more A theoretical description of isospin-forbidden analog resonances in direct reactions, using the K-matrix approach to analog resonances, is applied in numerical calculations for 207Pb(d,p)206 Pb(O+, ground state). Satisfactory agreement with the experimental data of Hamburger is obtained.
An improved method of calculating the fonn factor for the distorted-wave Born-approximation treat... more An improved method of calculating the fonn factor for the distorted-wave Born-approximation treatment of (p, alpha ) reactions is described that incorporates explicitiy the nuclear structure information. The improvement over earlier treatment of the (p, alpha ) reactions is achieved by carrying out a transformation to center-of-mass and internal coordinates of the transferred nucleons, whose individuai wave functions are calculated in a Woods-Saxon potential. The formalism is applied to an analysis of the reaction performed at a proton bombarding energy of 40.2 MeV. Relative proton spectroscopic factor are deduced for the relatively pure single-hole states at 0.0 (3/2/sup +/) and 2.52 (1/2/sup +/) MeV in /sup 39/K. Good agreement with the pro ton spectroscopic factors from the /sup 40/Ca(d, /sup 3/He)/sup 39/K reaction is ach ieved. The 5/ 2/sup +/ states in /sup 39/K whose structure is largely unknown contain components important to the (p, alpha ) reaction, but not to the (d, /sup 3/He) reaction, as evidenced by their relatively stronger excitation in the (p, alpha ) reaction. (auth)
The Communications section is for brief reports on completed research. A Comm'unication may be no... more The Communications section is for brief reports on completed research. A Comm'unication may be no longer than the equivalent of 2800~ords, i.e., the length to which a Physical Review Letter is limited. (See the editorial in the 21 December 1970 issue of Physical Review Letters.) Manuscripts intended for this section must be accompanied by a brief abstract for information retrieval purposes and, if they report on properties of particular nuclides, a key~ord abstract. Gamow-state analysis of r e(d, n) to proton resonances in Co 54 .
The inclusion of charge-exchange effects in direct-reaction theory is discussed and a nuniber of ... more The inclusion of charge-exchange effects in direct-reaction theory is discussed and a nuniber of experimental results are then treated: the threshold effect in ' Zr(fg, p) and 92Mo(d, p) excitation curves in the region of the (d, n) threshold to the. analog of the parent state, and the behavior of the Zr(d, np) and 9 Mo (d ep) total cross sections in the same region; Hamburger's data for 207Pb (d' p) 208Pb and, 6nally, the discrepancy between (fg, n) and (3He, d) spectroscopic factors for analog states in several light nuclei. The theory is successful in describing the threshold effect and Hamburger's data, but does not explain the discrepancy in spectroscopic factors. A number of methods of calculating the analog-residual-state wave functions are critically discussed. I. INTRODUCTIOÑ~H ERE now exists a considerable body of experimental al evidence'-" indicating that the (d, p) reaction channel leading to a given residual nuclear state is coupled to the (d, Il) reaction channel leading to the isobaric analog of the residual state excited in (d, p'). The simplest theory of such reactions, originally sketched. by Zaidi and von Brentano, " and quantitatively extended by Tamura and Watson, " requires replacement of the outgoing nucleon-nucleus state in the usual distorted-wave Born-approximation (DWBA) amplitude by the appropriate linear combination of solutions to coupled Lane equations. '4 The correctness of such an approach can now be given a fairly rigorous test, since a variety of experimental results is available. In Sec. II, we discuss the introduction of chargeexchange eGects into the usual DWBA theory. In Sec. III we discuss the general features of the (d, Il) threshold effect observed 111 (d, P) cxcltatloll clll'ves, 'tllc complementary (d, ep) data of Cue and Richard, " and the results of calculations. using the theory of * Research supported in part by the U.S. Atomic Energy Commission.
The first elastic-scattering analyzing-power (A) data at 0.8 GeV are presented and discussed. Ang... more The first elastic-scattering analyzing-power (A) data at 0.8 GeV are presented and discussed. Angular distributions of A over the range 2 to 20' (30 for C) have been obtained for C, 5 Ni,~Zr, and Pb using the high-resolution spectrometer at the Clinton P. Anderson Meson Physics Facility. The analyzing powers oscillate sharply over positive values in qualitiative agreement with expectations.
We present results of a phenomenologlcal analysis of recently obtained data for 4He + 4He elastic... more We present results of a phenomenologlcal analysis of recently obtained data for 4He + 4He elastic scattering at 0.65 and 0 85 GeV mmdent laboratory energms. We find that the observed angular dlstnbutmns cannot be fit unless the nuclear potential has a stron/~, short-range repulswe contribution, in agreement w~th the results of microscopic and phenomenologmal analyses of low energy 4He + 4He scattering.
An in-beam electron spectrometer was used to identify internal-conversion transitions resulting f... more An in-beam electron spectrometer was used to identify internal-conversion transitions resulting from proton bombardment of +Mo at 8.0 and 11. 0 MeV.
Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized ... more Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized protons from 40,42,44,48Ca are reported. A first-order, spin-dependent KMT optical potential analysis is presented from which the rms radii of the neutron densities are deduced. A comparison of these results with other determinations and with various theoretical predictions is given.
An analysis of the 4°At(r, t)4°K reactions populating the 0 + analog state at 4.38 MeV and the 0 ... more An analysis of the 4°At(r, t)4°K reactions populating the 0 + analog state at 4.38 MeV and the 0 + antianalog state at 1.65 MeV with incident 3He energies of 35 and 18 MeV is made, including contributions from a pickup-stripping reaction mechanism as well as a conventional direct reaction mechanism. Agreement in magnitude and shape between calculated and experimental cross sections is best when both mechanisms are allowed to contribute.
A theoretical description of isospin-forbidden analog resonances in direct reactions, using the K... more A theoretical description of isospin-forbidden analog resonances in direct reactions, using the K-matrix approach to analog resonances, is applied in numerical calculations for 207Pb(d,p)206 Pb(O+, ground state). Satisfactory agreement with the experimental data of Hamburger is obtained.
An improved method of calculating the fonn factor for the distorted-wave Born-approximation treat... more An improved method of calculating the fonn factor for the distorted-wave Born-approximation treatment of (p, alpha ) reactions is described that incorporates explicitiy the nuclear structure information. The improvement over earlier treatment of the (p, alpha ) reactions is achieved by carrying out a transformation to center-of-mass and internal coordinates of the transferred nucleons, whose individuai wave functions are calculated in a Woods-Saxon potential. The formalism is applied to an analysis of the reaction performed at a proton bombarding energy of 40.2 MeV. Relative proton spectroscopic factor are deduced for the relatively pure single-hole states at 0.0 (3/2/sup +/) and 2.52 (1/2/sup +/) MeV in /sup 39/K. Good agreement with the pro ton spectroscopic factors from the /sup 40/Ca(d, /sup 3/He)/sup 39/K reaction is ach ieved. The 5/ 2/sup +/ states in /sup 39/K whose structure is largely unknown contain components important to the (p, alpha ) reaction, but not to the (d, /sup 3/He) reaction, as evidenced by their relatively stronger excitation in the (p, alpha ) reaction. (auth)
The Communications section is for brief reports on completed research. A Comm'unication may be no... more The Communications section is for brief reports on completed research. A Comm'unication may be no longer than the equivalent of 2800~ords, i.e., the length to which a Physical Review Letter is limited. (See the editorial in the 21 December 1970 issue of Physical Review Letters.) Manuscripts intended for this section must be accompanied by a brief abstract for information retrieval purposes and, if they report on properties of particular nuclides, a key~ord abstract. Gamow-state analysis of r e(d, n) to proton resonances in Co 54 .
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